Application of LOPA analysis method in compressor stations of China-Russia Eastern Gas Pipeline and consideration

Abstract

In order to further promote the regional management mode of oil and gas pipelines, evaluate the adequacy of existing protection measures for the typical stations and enhance the risk control capability thereof, the safety integrity level(SIL) of the functional loops of the station safety instrumentation system(SIS) was evaluated, by calculating the occurrence frequency of residual risks with the layers of protection analysis(LOPA) method, based on the comprehensive hazard and operability analysis(HAZOP). LOPA analysis was performed on the low-risk point of compressor inlet flow of one compressor station in China-Russia Eastern Gas Pipeline. The results show that: only the environment impact of the risk point without considering the protection of compressor body can meet the risk tolerance criteria, but personnel casualties, economic loss and reputation effect do not meet the risk tolerance criteria. The auto-stop protection of highhigh interlock for shaft vibration, displacement and others of compressors should satisfy the requirements of SIL2, and the risk reduction capability should not be less than 464. Generally, LOPA analysis can effectively solve the deficiency that the residual risk cannot be quantified in HAZOP analysis, and evaluate whether the existing layer of protection can reduce the risk to the tolerance standard, so as to provide experience reference for SIL rating of relevant natural gas compressor stations. At the same time, some management suggestions were put forward for the shortcomings of LOPA analysis and SIL rating in oil and gas pipeline industry.

Keywords

• lopa
• compressor stations
• safety instrumentation system(sis)
• risk tolerance criteria
• compressors